There is not a motorized Ile-de-France resident who has not, one day, taken this route, without suspecting that he was crossing an engineering monument. This seemingly innocuous infrastructure is the A86 duplex which, since 2011, has linked Rueil Malmaison to Vélizy. This short 10 km motorway was, at the time of its inauguration, unique in the world for several reasons and in particular for the avalanche of figures which today earned it the honors of a documentary broadcast on RMC Découvertes (Canal 24 of TNT ) on March 7th.
Because if the duplex in question inherits this funny name, it is not without reason. The tunnel is actually a huge and unique double-decker tube. Thus, the cars do not cross there and are superimposed in one direction as in the other on the two times two voices that compose it. A prank of engineers? It is rather the only possible solution, and retained since the beginning of the work in 1999.
Ten years of pharaonic works
Because the passage of such a tunnel, the largest in France, in the corner of the densest hexagon, posed some minor problems for Cofiroute, the subsidiary of Vinci which was equipped with a chef’s helmet site for 11 years to complete the operation. This is because the route taken by the infrastructure is not only covered with buildings, but it borders on the Palace of Versailles, hence the obligation to go through a tunnel dug as deep as possible, and which is the narrower as possible. The duplex quickly imposed itself.
Trouble also quickly set in. After a challenge by local residents in the courts, and a fire that blocked 19 workers, who escaped unscathed at the bottom of the tunnel, all the safety of the infrastructure is to be reviewed. Because in 1999, another huge fire killed 39 people in the middle of the Mont Blanc tunnel, shutting down all the major French tunnels to tighten standards. The A86 construction site is one of them. But Emma continues her job. Emma? This is the small name of an enormous machine, a steel tunnel boring machine 200 meters long and weighing 3,000 tons which digs 90 meters underground for the ten kilometers of the section, under 9 different geological layers.
“The Executive Highway”
In 2011, the tunnel was inaugurated and it now provides access to the most expensive motorway in France: the A14. It was quickly renamed the executive highway, since it allows white-collar workers living in the western suburbs to get to their Parisian offices or to La Défense without wasting too much time in the endless traffic jams of the A13. Executives who, for some of them, can take this section because they have a company car, and above all, in this specific case, a professional card allowing them to pay the toll. Because the price, which varies according to the state of the traffic, can reach 13 euros at peak times. Expensive, if you take this section between Orgeval and La Défense morning and evening. Especially since the journey is brightened up by no less than 12 automatic speed cameras. You have to pay for Emma’s retirement.
